1. Field of the Invention
The present invention relates to a secondary battery and a capacitor, more particularly utilizing an indole compound as an active material of an electrode and a proton as a charge carrier.
2. Description of the Related Art
Indole polymers are known as excellent materials for an active material of electrode in the light of electromotive force and capacity. However, the battery wherein the indole polymers are utilized as an active material has not been satisfactory in the light of a rapid charge and discharge and a cycle characteristic.
The inventors of the present invention have already proposed an electrochemical cell by Japanese Patent Application Number 2000-282309, wherein trimer compounds of indole or indole derivatives are utilized as an active material of electrode, and have studied further improvement of the performance of the cell since then.